/**
 * Inline assembler implementation for DMD.
 * https://dlang.org/spec/iasm.html
 *
 * Copyright:   Copyright (C) 2025-2026 by The D Language Foundation, All Rights Reserved
 * Authors:     Walter Bright
 * License:     $(LINK2 https://www.boost.org/LICENSE_1_0.txt, Boost License 1.0)
 * Source:      $(LINK2 https://github.com/dlang/dmd/blob/master/compiler/src/dmd/iasmaarch64.d, _iasmaarch64.d)
 * Documentation:  https://dlang.org/phobos/dmd_iasmaarch64.html
 * Coverage:    https://codecov.io/gh/dlang/dmd/src/master/compiler/src/dmd/iasmaarch64.d
 */

module dmd.iasm.dmdaarch64;

import core.stdc.stdio;
import core.stdc.stdarg;
import core.stdc.stdlib;
import core.stdc.string;

import dmd.astenums;
import dmd.astcodegen;
import dmd.declaration;
import dmd.denum;
import dmd.dinterpret;
import dmd.dmdparams;
import dmd.dscope;
import dmd.dsymbol;
import dmd.errors;
import dmd.expression;
import dmd.expressionsem;
import dmd.funcsem : checkNestedReference;
import dmd.globals;
import dmd.id;
import dmd.identifier;
import dmd.init;
import dmd.location;
import dmd.mtype;
import dmd.parse;
import dmd.statement;
import dmd.target;
import dmd.tokens;
import dmd.typesem : pointerTo, size, isIntegral;

import dmd.root.ctfloat;
import dmd.common.outbuffer;
import dmd.root.rmem;
import dmd.rootobject;

import dmd.backend.cc;
import dmd.backend.cdef;
import dmd.backend.code;
import dmd.backend.x86.code_x86;
import dmd.backend.codebuilder : CodeBuilder;
import dmd.backend.global;
import dmd.backend.iasm;

/************************
 * Perform semantic analysis on InlineAsmStatement.
 * Params:
 *      s = inline asm statement
 *      sc = context
 * Returns:
 *      `s` on success, ErrorStatement if errors happened
 */
public Statement inlineAsmAArch64Semantic(InlineAsmStatement s, Scope* sc)
{
    static if (1)
    {
        printf("InlineAsmAArch64Statement.semantic()\n");
        for (auto token = s.tokens; token; token = token.next)
        {
            printf("TOK.%s %s\n", token.toString(token.value).ptr, token.toChars());
        }
    }

    const bool doUnittests = global.params.parsingUnittestsRequired();
    scope p = new Parser!ASTCodegen(sc._module, "", false, global.errorSink, &global.compileEnv, doUnittests);

    /* Set list of tokens that will be the input to the parser, and starting line number to use.
     */
    p.setTokenList(s.tokens, s.loc.linnum);

    int errors;
    static if (1)
    {
        if (p.token.value == TOK.identifier)
        {
            if (p.token.ident == Id.naked)
            {
                s.naked = true;
                sc.func.isNaked = true;
                p.nextToken();
            }
            else if (p.token.ident == Id.op)
            {

                p.nextToken();
                Expression exp = p.parseAssignExp();
                // Must evaluate to a constant, like an enum member does
                exp = exp.expressionSemantic(sc);
                exp = resolveProperties(sc, exp);
                exp = exp.ctfeInterpret();
                if (exp.op == EXP.error)
                    return new ErrorStatement();

                //printf("expression: %s\n", exp.toChars());
                Type t = exp.type;
                if (!(size(t) == 4 && isIntegral(t)))
                    error(s.loc, "size of opcode must be 4 of integral type\n");
                code* pc = code_calloc();
                pc.Iflags |= CFpsw;            // assume we want to keep the flags
                pc.Iop = cast(int)exp.toInteger();
                s.asmcode = pc;
            }

            if (p.token.value != TOK.endOfFile && !errors)
            {
                error(s.loc, "end of instruction expected, not `%s`", p.token.toChars());
                return new ErrorStatement();
            }
            else
                return s;
        }
    }

    /* For example,
     *  asm { str w3,[x2,x4]; }
     * would come through as:
     *  TOK.identifier TOK.identifier TOK.comma TOK.leftBracket TOK.identifier TOK.comma TOK.identifer TOK.rightBracket
     * and it is matched to the grammar for the "str" instruction:
     * https://www.scs.stanford.edu/~zyedidia/arm64/str_reg_gen.html
     * It then calls INSTR.str_reg_gen(sz=0,Rindex=4,extend=3,S=0,Rbase=2,Rt=4)
     * which returns 0xB8_24_68_43 which is installed in c.Iop.
     * (c is a code*.)
     * Symbols and values are put in c.IFL1 and c.IEV1.
     * s.asmcode is then set to c.
     * Matching the list of tokens to an instruction is straightforward, however, the trouble
     * is the very large and diverse number of instructions. The challenge is to boil this
     * complexity down to a simple table.
     */

    error(s.loc, "AArch64 inline assembler not implemented (yet!)");
    return new ErrorStatement();
}
